An effective pulse-shaping technique for testing stainless steel alloys in a split-hopkinson pressure bar

Pulse shaping techniques are an integral component of designing and executing valid Split-hopkinson pressure bar (SHPB) experiments. Proper pulse shaping is vital for achieving stress equilibrium and a constant strain rate within the dynamically tested sample. A systematic method based on two-dimensional finite element (FE) analysis was developed to design an optimized single material pulse shaper for SHPB testing of two stainless steel alloys. The tested alloys exhibit high strain-hardening, but have significantly different mechanical properties: Lean Duplex Stainless Steel 2101 (LDSS 2101) and austenitic stainless steel 316L. Results show that pulse shapers made of LDSS 2101 are capable of satisfying stress equilibrium and constant strain rate conditions for the studied materials at different strain rates regimes. The outlined FE analysis workflow is an effective approach to define the optimal dimensions of pulse shapers without the need for costly pulse-shaper-development experimental trials.